Abstract : A method is developed to describe and to control the data traffic in a variety of storage devices by the structure of the program. The key idea is to abandon the assumption that declaration of a variable causes storage allocation in main store; instead a variable can reside on an arbitrary storage medium as specified by the declaration. The block concept of ALGOL 60 is extended so as to allow control of main and backup stores by stack mechanisms. The method is compared with own variables in ALGOL 60, input output variables described by Hoare, and paging schemes in multiprogramming and timesharing. A timesharing design with storage management based on the proposed scheme is sketched briefly. (Author)